Volunteers will be recruited from girls attending the IPC clinic. We will only recruit female children as calcium metabolism & bone growth is of special concern in females & we only have control data on calcitropic hormones & bone mineral density in female children. There are currently approximately 81 HIV-infected children between the ages of 5-17 years who receive care in the IPC clinic. Given excellent participation in previous nutrition related protocols, we anticipate that we should achieve a sample size of 20 females in this age group. Over 90% of the HIV-infected children are African-American. All data collected will be compared to age & race matched girls as calcipropic hormones, bone density & calcium kinetics significantly differ between black & white girls.